The present invention relates to a video tape recording apparatus using a Hadamard transformation system for recording and reproducing a video signal.
A recently introduced video tape recording apparatus utilizes a system which distributes a video signal to a plurality of channels and the distributed video signals are recorded and reproduced by a plurality of fixed type magnetic heads. This is the so-called Hadamard transformation system.
In such a video tape recording apparatus, however, input information is converted into a time series signal of n phases for the purpose of obtaining an Hadamard transformation signal, and then, the input signal is sampled.
In case of such recording and reproduction, it is not only necessary to record and reproduce a Hadamard transformation signal but also necessary to record and reproduce a sampling signal with an independent channel or by multiplexing or the like.
In recording and reproducing a sampling signal, however, it is difficult to precisely transmit phase information from the recording system to the reproducing system if FM modulation is used for example, phase distortion of the FM transmission system may undesirably shift the phase of the demodulated sampling signal relative to the Hadamard transformation signal.
Therefore, using a sampling signal having an unstable phase at the time of Hadamard transformation may significantly deteriorate the picture quality.